Automatic starting mechanism



Nov. 8, 1938. L. K. LOEHR ET AL.

AUTOMATIC STARTING MECHANISM Filed May 28, 1932 Burdlafi 11v VENTORS aehr'w/ 6.

A TTORNE y llesleflL Patented Nov. s, 1938 UNITED STATES PATENT OFFICE AUTOMATIC STARTING MECHANISM Nevada Application May 28, 1932, Serial No. s14,zzo

9 Claims.

This invention relates to automatic starting mechanism for internal combustion engines and more particularly to an automatic control for actuating a starting mechanism upon closure of a manual switch such as the ignition switch of the engine, and for reactuating the same in case of engine stall as long as said switch is left closed.

In automatic starting control systems it is desirable to provide for steady and continuous cranking until the engine starts in order to avoid the possibility of premature disengagement of the starting pinion. At the same time, it is desirable to insure that the starting mechanism be not reactuated by slowing down of the engine even to speeds well below cranking speed since it may happen that the idling speed of the engine is lower than the cranking speed, and during fluctuations or rolls the engine may 20 almost'come to rest. It has also been found desirable to restrict the spinning of the starting motor after disengagement from the engine member so that particularly in case of a false start, the reenergization of the starting motor Will be effective to traverse the pinion into mesh with the flywheel gear, which might nothappen if the starting motor were still spinning rapidly at the time of its reenergization.

It is accordingly an object of the present invention to provide a novel automatic starting mechanism arranged to crank continuously and steadily until the engine starts and then to release the starting mechanism positively.

It is another object to provide such a device in which reengagement of the starting mechanism while the engine is self-operative is effectively prevented.

It is a further object to provide such a device in which a plurality of products of self-operation of the engine are used in conjunction to supplement each other in preventing engagement of the starter.

It is another object to provide such a device embodying provisions for restricting spinning of the starting motor by momentum after the starting switch has been opened.

Further objects and advantages will be apparent to those skilled in this art from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a semi-diagrammatic illustration of one preferred form of the invention showing the parts in normal or idle position; and

Fig. 2 is a similar view of a second embodiment of the invention.

Referring first to Fig. 1 of the drawing, there is illustrated a starting system for an internal combustion engine, not shown, comprising a battery I, grounded at 2 and connected by a lead 3 to an electro-magnetic starting switch 4 which in turn is connected by a lead 5 to a control relay structure indicated generally by the numeral 6. Relay 6 includes a series coil 1 connected to the lead 5 and connected by a lead 8 to the starting motor SM which is grounded at 9 to complete the starting circuit.

A control circuit for the starting switch 4 is illustrated comprising a solenoid ll energized from the battery I through a manual switch I2 which may, as indicated, be the ignition switch of the engine, and connected by a lead l3 to a circuit making and breaking device including a fixed contact l4 and a cooperating movable contact l5. Contact I5 is mounted on an armature l6 pivoted at I! and extending in proximity to an adjustable pole piece I8 energized by the series coil I to maintain contacts l4, I5 closed during cranking. A spring 2| is arranged to normally maintain contact I5 in engagement with contact l4, and the armature I6 is grounded as indicated at I9 in order to complete the control circuit.

Fluid-pressure means responsive to rotation of the engine are provided for moving thearmature 16 to open contacts l4, l5 when the engine starts, in the form of a lever 22 also pivoted on the bearing l1 and yieldably connected to the armature I6 by means of a spring 23. Means are provided for moving the lever 22 in a direction to tension the spring 23 and urge the armature IE to open position, in the form of a rod 24 traversing the end of the lever 22 and adjustably and yieldably connected thereto as by means of a spring 25 and adjustable abutment 26. The rod 24 is arranged to be actuated by a flexible diaphragm 21 which is subjected to fluid pressure within a chamber 28 connected by suitable means such as a conduit 29 to a source of fluid pressure produced by rotation of the engine. This fluid pressure may be oil or water pressure from the lubricating or cooling systems of the engine, or may be exhaust pressure, or vacuum from the engine intake or a vacuum pump. As here illustrated, the diaphragm 21 is arranged to be drawn downwardly by vacuum.

In the operation of this form ofthe invention, starting with the parts in the positions illustrated, closure of the ignition switch l2 completes the control circuit through the starting switch magnet II and contacts l4, l5 to the ground at I! whereby said starting switch 4 is closed and the starting circuit completed through the series coil 1 and starting motor SM. Rotation of the engine during cranking causes air pressure to act on the diaphragm 21, depressing said diaphragm and causing the lever 22 to move downward, placing a tension on the spring 23 tending to open contacts i4, i5. At this time, however, the series coil 1 is strongly energized by the cranking current whereby the armature i6 is maintained in its closed position by the attraction of the pole piece l8.

When the engine starts, the release of the load on the starting motor reduces the current flow whereby the series coil 1 is weakened and the spring 23 becomes effective to open contacts l4, l5 and maintain said contacts open as long as the engine continues to run. If the engine should stall, the release of the fluid pressure on the diaphragm 21 allows the parts of the relay to return to their normal positions, thus reclosing the control circuit and causing the starting operation to be repeated.

In Fig. 2 there is illustrated a second embodiment of the invention in which a plurality of products of engine rotation are utilized to jointly control the starting relay. As here shown, the elements of the starting circuit and the relay circuit are the same as in Fig. 1 and are similarly numbered. A control relay 30, however, is provided embodying a rigid armature and lever member 3| pivoted at 32 and provided with a depending arm 33 fixed thereto in order to carry the movable contact I5 of the relay circuit. One end 34 of said armature member 3| is arranged in proximity to the adjustable pole piece ll of the series coil 1, while the opposite end 35 of said member is arranged to engage a stop 36 on a rod 31, being yieldably urged into engagement therewith by suitable means such as a spring 38.

The rod 31 is arranged to be actuated by a pair of flexible diaphragms 39 and 4| which are subjected to the action of fluid pressures generated by separate components of the engine to .be started, or its auxiliaries. As here shown, the diaphragm 39 is arranged to be subjected to vacuum within a chamber 42 which is connected by a conduit 43 to a source of vaccum such as the engine intake or an engine-driven vacuum pump, while the diaphragm 4| is arranged to be subjected to fluid pressure within a chamber 44 connected by a conduit 45 to a source of power such as exhaust pressure, lubricating oil pressure or circulating water pressure. It will thus be seen that the two diaphragms 39 and 4| are arranged to act jointly under the operation of different products of engine rotation to control the action of relay 30.

In this embodiment of the invention, means are provided for restricting the free spinning of the starting motor after the starting switch is opened. As here shown, this means is in the form of a hand brake 46 anchored at 41 to the frame of the motor SM and arranged to cooperate with a brake drum 48 mounted on the end of the armature shaft 49. The brake 46 is normally held in engagement with the drum 48 as by means of an adjustable spring 5| which is arranged to press the ends 52 and 53 of the brake band together. Means are provided for releasing the brake when the starting motor is actuated in the form of a releasing cam 54 actuated by a lever 55 flxed on the cam shaft 56, said lever being connected by a link 57 to the starting switch member 4 in such manner that closure of the switch 4 swings the arm 55 in a direction to cause the cam 54 to release the brake. Means such as a spring 53 is provided for returning the lever 55 to normal position as defined by a stop 53, when the switch 4 is open.

In the operation of this form of the invention, closure of the ignition switch l2 completes the relay circuit through the starting switch coil II and contacts l4, l5 whereby the starting switch 4 is closed, releasing the brake 46 from the drum 48 of the starting motor and closing the starting circuit through the series coil I and the starting motor. During cranking,thevacuum in the chamber 42 and pressure in the chamber 44 cause diaphragms 39 and 4| to flex downwardly, thus moving the rod 31 down and causing the spring 38 to urge the armature member 3| in a direction to open contacts 4 and I5. At this time, however, the heavy cranking current energizing the coil 1 causes the pole piece IT to be magnetized sufliciently to prevent movement of the armature member 3| and maintain contacts I4, l5 closed. When the engine starts, the weakening of the coil I due to the relief of the cranking load allows the armature member 3| to be moved by the spring 38 to open contacts l4, l5, said contacts being maintained open as long as either of the diaphragms 39 or 4i is subjected to fluid pressure by reason of the rotation of the engine.

The opening of the relay circuit causes the starting switch 4 to open, whereupon the motor is deenergized and the brake 46 applied thereto, whereby the starting motor is immediately brought to rest. In case of a false start, therefore, the motor is brought substantially to rest before the reclosure of the starting circuit due to the failure of fluid pressure on the diaphragms 39 and 4|. The reactuation of the starting motor consequently causes rapid acceleration thereof whereby the traversal of the pinion into mesh with the engine gear is assured.

Although but two embodiments of the invention have been shown and described in detail, it will be understood that other embodiments are possible and that various changes may be made in the construction and arrangement of the parts without departing from the spirit of the invention as defined in the claims appended hereto.

What is claimed is:

1. In an automatic starting mechanism for internal combustion engines, a starting circuit including an electro-magnetic starting switch, a conrol circuit for said starting switch including contacts for opening or closing said control circuit, means energized by cranking current for causing said contacts to maintain the control circuit closed, and fluid-pressure operated means responsive to rotation of the engine for overcoming said maintaining means and causing said contacts to open said control circuit when the engine starts and to maintain said circuit open as long as the engine is self-operative.

2. In an automatic starting mechanism for internal combustion engines, a starting circuit including an electro-magnetic starting switch, a control circuit for said starting switch including contacts for opening or closing said control circuit, electro-magnetic means energized by cranking current causing said contacts to maintain the control circuit closed, and means including a plurality of fluid-pressure means cooperating in response to rotation of the engine to cause said contacts to open said control circuit when the engine starts and to maintain said circuit open as long as the engine is self-operative.

3. In an automatic starting mechanism for internal combustion engines a starting circuit including a magnetic starting switch, a control circuit for said magnetic switch including a pair of normally closed contacts, electro-magnetic means energized by cranking current for holding said contacts closed during cranking, and means operated by fluid pressure responsive to engine rotation for applying a predetermined force to open said contacts, said force being effective to overcome the holding means when the cranking load is relieved by the starting of the engine.

4. In an automatic starting mechanism for internal combustion engines a starting circuit including a magnetic starting switch, a control circuit for said magnetic switch including normally closed contacts, electro-magnetic means energized by cranking current for holding said contacts closed during cranking, and aplurality of complementary fluid-pressure means responsive to engine rotation cooperating to overcome said holding means and open said contacts when the engine starts and hold them open under all conditions of self-operation of the engine.

5. In an automatic starting mechanism for internal combustion engines, a starting circuit including a magnetic starting switch, a control circuit therefor including a pair of contacts, means for holding said contacts closed during cranking, and means responsive to rotation of the engine for opening said contacts, said opening means including a movable element, means energized by fluid pressure generated by rotation of the engine for moving said element, and a yielding connection between said element and said contacts.

6. In an automatic starting mechanism for internal combustion engines, a. starting circuit including a magnetic starting switch, a control circuit therefor including a pair of contacts, means responsive to the cranking current for holding said contacts closed during cranking, and means responsive to rotation of the engine for opening said contacts, said means including a movable element, means energized by fluid pressure generated by rotation of the engine for moving said element, and a yielding connection between said element and said contacts, said connection being stressed by said movement whereby weakening of the holding means when the engine starts enables said connection to open said contacts.

7. In an automatic engine starting system, a starting circuit including a starting motor and a magnetic starting switch, means for closing said switch in case of engine stall, and for opening said switch when the engine starts, and means controlled by said switch for opposing spinning of the starting motor.

8. In an automatic engine starting system, a starting circuit including a starting motor and a magnetic starting switch, means for closing said switch in case of engine stall, and for opening said switch when the engine starts, means for opposing spinning of the starting motor when the switch is opened, and means for releasing said opposing means when the switch is closed.

9. In an automatic engine starting system, a starting circuit including a starting motor and a magnetic starting switch, means for closing said switch in case of engine stall, and for opening said switch when the engine starts, a brake for said starting motor, means for applying the brake when the starting switch is opened, and means for releasing said brake when the starting switch is closed. LESLIE K. LOEHR.

WAYNE E. BURDICK. 

